One of known semiconductor memory devices is a NAND flash memory (hereinafter, referred to as a NAND memory) in which a plurality of memory cells are connected in series to each other to form a block. The NAND memory has drawn attention as a non-volatile semiconductor memory device capable of achieving high integration and high capacity.
In the NAND memory, data is written and read in the unit of a predetermined amount of data which is called a page. In the NAND memory, when data is read, a sense amplifier fixes data stored in the memory cell for each page, and the data is stored in a data register, read from the data register and is then transmitted to the outside.